


Dirty Daddy - Part 12

by DirtyKnots



Series: Kinktober 2019 [12]
Category: Teen Wolf (TV)
Genre: Anal Fingering, Anal Sex, Bestiality, Comeplay, Derek is Stiles' father, Extremely Underage, Father/Son Incest, Felching, Incest, M/M, Outdoor Sex, Rimming, Shota, Shota Stiles Stilinski, Shotiles, Watersports, piss drinking, piss fucking
Language: English
Status: Completed
Published: 2019-10-12
Updated: 2019-10-12
Packaged: 2020-12-13 22:38:02
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 2,558
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21005303
Author URL: https://archiveofourown.org/users/DirtyKnots/pseuds/DirtyKnots
Summary: Kinktober 2019: Day 12 - RimmingCuriousCat Anon Prompt: In the dirty daddy verse, maybe Stiles, Derek, and Roscoe form a triangle where they suck each other off/rim each other. To finish, Stiles fucks Roscoe while his dad is fucking him.





	Dirty Daddy - Part 12

They've been ridiculously busy since Stiles' school year finished. Derek had so much paperwork to sort out to make sure he was able to homeschool Stiles, and then there was the new house he'd bought - several modifications happening before it was ready for move in. Sure, they could've stayed where they were, but Derek was tired of worrying about nosy neighbors and prying eyes. He'd found the perfect place, a few counties over from where they lived now.

It was a large single story, set a little deeper against a nature preserve. There weren't any neighbors in close proximity, most of them at least a half mile out or further. The property itself was enclosed by a ten foot fence, something the previous owner had installed to keep the deer out, and it was solid construction, privacy completely ensured by the tight press of the slats. It had a few rooms, an open plan living room-kitchen-dining room, a detached garage, and a basement.

Setting it up took some work, the flooring had to be ripped out and replaced with easier to clean laminate and faux wood, the bathrooms expanded, unimportant walls knocked down to allow for a more open plan, more light and windows. Derek ordered new furniture too, a vinyl living room set, a bigger and lower master bed, everything designed to be easier for his son and their dog to access. The delivery and set up had happened at the start of the week, and Derek had picked up a few things on his own as well from specialty stores - most importantly the vinyl bed covers. One for the twin bed on Stiles' room, though he didn't anticipate it would see much use, it was more of a precaution on the off-chance they had visitors. With Stiles being homeschooled now and their house being further away from any potential neighbors, Derek planned to let Stiles move into his room. Their room now, really. He also got a vinyl bed cover for their bed, not wanting to have to replace the mattress too frequently.

They'd moved in a few days after the furniture had arrived, unpacking and setting up the house, and hadn't had much time at all to play. Or at least Derek hadn't. He knew Stiles and Roscoe had still been having fun, and he was sad that he only caught snippets of it, but by the time his work was done each day and he unpacked whatever he could, he was too tired for anything beyond a few kisses or a quick blowjob when he couldn't say no to his son. 

Everything was finally done though, and Saturday dawned bright and clear with Derek finally having gotten enough sleep. There was no work to be done and he had an entire day to just enjoy his new home with his family. Stiles and Roscoe were still asleep when Derek climbed out of bed, slipping on a pair of boxer briefs and going to make himself a cup of coffee. The day was already warm, the house heating from all of the natural light, and he'd just filled his mug when Stiles came in, rubbing his eyes and yawning, Roscoe on his heels. 

"Gotta pee daddy." Stiles was so used to their morning routines that he came to Derek first, despite him not having had time to indulge in drinking his son down for the last week.

"Mmm, why don't we head out into the backyard baby, have our morning drinks in the sunshine."

"We can?" Stiles perked up a little at that, because he knew the most important rule was to never do anything outside.

"We can. That's why daddy bought this house. We have a nice big yard for when we want to play outside and nobody can bother us at all." Derek smiled and ran his fingers through Stiles' hair when his son plastered his little naked body against his shins in a hug before darting to the backdoor. Derek reached past him and unlocked it, following more sedately after Stiles and Roscoe shoved themselves out the door. The sun felt good on his skin as he watched his son and dog run in circles around the yard before Roscoe lifted a leg, Stiles falling to his hands and knees instantly to get his mouth on the dog's sheath. Derek moved closer, watching his son's throat work as he swallows down the dog's morning piss.

Derek strips off his underwear, tosses them back toward the porch, his cock chubbing up as he watches Stiles piss himself while still drinking from the dog, little thighs glistening in the sun as it runs down his legs. It's a shame he won't be able to have a taste, but he's sure Stiles will have to go again soon enough. Especially when Derek adds to his filling belly with his own morning piss. Stiles doesn't even hesitate when Derek is close enough, letting Roscoe's sheath pop from his mouth, a final spurt of piss spraying him in the face before he crawls over to his daddy and kneels up to take Derek's cockhead in his mouth. Derek's hand cups his face, thumb rubbing over his cheek.

"My beautiful baby boy, so good for daddy and Roscoe. Your belly getting all full and sloshy baby?" Stiles nodded with Derek's cock still in his mouth, a steady stream being swallowed by his son. The more his bladder emptied, the fatter his cock got, until Stiles was forced to let it fall from his mouth. Derek lifted his son up after that, pulled him into a kiss, sucking on the boy's tongue and feeling his son's cocklet stiffen against his abs. He deepens the kiss and let's Stiles rut against him for a few minutes before setting the boy back on his feet. The sun makes Stiles' skin seem like it's shining and Derek can't help but rub his hands over him, feeling his pert ass up and parting Stiles' cheeks when Roscoe comes sniffing, leaning over to watch that rough tongue slide up Stiles' cleft for a moment. 

"You look so pretty out in the sun baby, daddy wants a taste too. You want daddy to lick your hole? And you can lick Roscoe's okay?"

"'Kay! Can Roscoe lick yours too daddy?" 

"Sure baby, that sounds good." Derek helped Stiles get on his hands and knees at an angle where he could turn his head sideways to get to the dog's hole, making sure Roscoe knew to stay (not that it was an issue, Roscoe enjoyed it as much as they enjoyed doing it). Once they were in place, Derek just watched for a minute, loving seeing his boy's small tongue pushing past that furred pucker, licking and thrusting and slurping at the dog's hole. He almost changed his mind, almost put his mouth next to Stiles', but there was always later. For now he wanted to get Stiles loose and relaxed, eat that boyhole he loved.

It took a little maneuvering to get himself positioned so that Roscoe could lick his ass while he ate Stiles' hole, but eventually he got there, tongue swirling and dipping in, feeling his son's body open around him. Soon the yard was filled with the sounds of licking and sucking, the three of them getting worked up as they tasted each other, Derek's cock dripping a steady stream of pre onto the grass. It was even better when he shifted his balance to one hand, bringing the other up to push inside of Stiles, loving how relaxed his son's ass was, letting him fuck his finger in and out. He lifted his mouth away when he felt Stiles shifting around, thought maybe he needed to piss again and wanted to enjoy it this time, but instead he was greeted by the sight of Stiles doing the same to Roscoe, two of his small fingers pushing inside the dog's hole, squelching through the spit it was soaked in. 

Derek cursed himself for not having the foresight to bring lube out here, suddenly dying to sink his cock into his son while the boys fucked their dog. He pulled all the way off, standing and waving Stiles back when it looked like he was going to stand as well.

"Stay here baby, daddy's just gonna get some lube so we can keep playing. Wanna see you put your little cock inside of Roscoe while I fill you up with my daddy cock, okay?" Stiles didn't take his mouth off the dog, just hummed his agreement and kept plunging his tongue and fingers inside of the dog. Derek watched for another minute before he managed to tear himself away to hurry inside and grab a bottle of lube from a drawer in the kitchen. At least he'd had enough foresight to stash lube all over the house. 

By the time he's back outside, Stiles and Roscoe have both shifted, Roscoe no on his back as Stiles sucks on the cock that had poked free of his sheath. Derek groans and palms himself as he moves back over to them. He can see that Stiles still has two small fingers in the dog's hole so he leans over them first, drizzling lube down over Roscoe's pucker and watching as Stiles fingerfucks it into him. He takes it on himself to lube Stiles' cocklet, fondling him as he makes sure there's plenty before he directs his attention to Stiles' hole. 

The ring of muscle feels soft and supple under his fingers, spreading open easily for him now that they've done this so often, and he doesn't need to check much to be sure his son is ready for his cock. When he's certain that Stiles will be able to take him, he slicks himself and lines his cock up, body dwarfing his son's as he leans over him and begins a slow and steady push inside, relishing how tight his boy's hole is around him. He doesn't stop until his cock is fully sheathed. 

Derek needs a moment to just breathe, still overwhelmed by getting to push all the way inside of his son, getting to feel that small body clench around him. As soon as he's sure he won't come right away, he adjusts his position, slipping a hand down underneath Roscoe and propping the dog's ass up enough for Stiles to be able to get his cocklet inside. 

"Okay baby, hold your cock just like daddy usually does. Good, yeah, just like that. Now line it up with Roscoe's hole and push in slow, you don't want to hurt him." Derek groans as he watches Stiles' cocklet push inside of Roscoe's ass, barely any more of a stretch than his two fingers had been, and he follows Stiles' body with his own, making sure he doesn't slip out. Once Stiles is fully inside the dog, Derek pulls out an inch, feeling the way his son's hole clings to his cock. "Go on baby, start fucking. Push yourself back on daddy's cock while you pull out of Roscoe, fuck us both baby." 

Stiles does his best to follow his daddy's advice, pulls out and pushes back in, sliding his hole over Derek's cock as he thrusts away inside of the dog. It's quick but too shallow to get Derek off, though it feels amazing to feel the drag and stretch of Stiles' ass around him. He lets Stiles rut away inside of Roscoe, the dog not seeming to mind, his fat dog cock getting wet and sticky at the tip, until Stiles shudders beneath him and he knows his son is coming dry, little cocklet overstimulated. Derek can see the way Stiles is scrunching up his eyes, watch when his son brings a hand up to push at his little belly, and knows the boy is flooding the dog's ass with his piss, a mockery of coming inside the dog, but one he's sure they'll both enjoy sucking out of Roscoe. 

As soon as Stiles is done, his little body relaxing more, Derek lets Roscoe's ass settle back onto the grass, using that hand to pull Stiles all the way back onto his cock and knee walking them back enough that they can push their faces down to Roscoe's hole. Derek has to contort himself more than Stiles, but it's worth it when he can fuck harder inside of his son as they both lap at the piss leaking out of Roscoe's furred pucker. It doesn't take long at all for Derek to get close, the slide of his son's tongue over his as they both push them inside of Roscoe's ass enough to tip him over the edge, and he grinds his way through his orgasm, filling Stiles up with his warm come.

When he finishes, he pulls up and off, lifts a mostly worn out Stiles to his hands and knees, calling Roscoe over. Stiles is stretched and loose and leaking out come and he helps the dog mount his son, loving the way his boy looks with the dog looked over him, his angry red rocket poking at Stiles' thighs as he tries to find his hole. Derek only has to reach forward and give a little help and then Roscoe is shoving in, making Stiles cry out at the force of it.

"Okay baby or too much?"

"Okay daddy. Feels...oh, oh oh." Stiles loses his train of thought but it's okay, he's not trying to get away or crying so Derek settles in to watch, almost wishing he hadn't come yet, watching as the knot starts to swell and knowing he's finally going to get to watch his boy take it. The popping as it forces its way in and out of Stiles' rim before it catches is obscene in the quiet of the late morning, even more so because they're outside, where anyone could hear or see if they climbed the fence, but it just makes it better. Stiles does cry a little when the knot locks and Roscoe tugs a few times before giving in and grinding instead of trying to thrust, but Derek pets his face and hair, murmurs soothing words and kisses away the tears until Stiles has calmed and relaxed, grinding back and clenching his ass down around Roscoe at Derek's urging.

Derek can see a slight swell to Stiles' belly, realizes the dog is pumping him so full of come that Stiles almost looks pregnant with it, and his cock gives a feeble twitch. He'll need to dig out the plug when they go inside, wants to see how much more he and the dog can fill Stiles up. He'll have to use his fingers on the way there, but it's not like that's a hardship. As much as he'd love to crawl beneath them, encourage Stiles to sit on his face and push out that bellyful of come, he'd rather see how full he can make him, knows Stiles will be up for it - he's always up for anything his daddy wants. Not for the first time, Derek is glad that he decided to move them, glad he decided to homeschool, can't wait to see how much more they can have together now that they don't have to pretend most of the time.

**Author's Note:**

> Come prompt me on [CuriousCat](https://curiouscat.me/dirtyknots).  
All of my additional contact information can be found on my [Profile Page](https://archiveofourown.org/users/DirtyKnots/profile)!


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